为什么我会得到在 SQLAlchemy 模型中定义的列的 NameError

Question

我正在使用 Flask 开发 REST API。其中一张表建模如下：

class AudioSessionModel(db.Model):
    __tablename__ = 'audio_session'
    id = db.Column('audio_session_id', db.Integer, primary_key = True)
    cs_id = db.Column(db.Integer)
    session_id = db.Column(db.Integer)
    facility = db.Column(db.Integer)
    description = db.Column(db.String(400))

    def __init__(self, cs_id, session_id, facility):
        self.cs_id = cs_id
        self.session_id = session_id
        self.facility = facility

业务逻辑在 DAO 中定义class:

class AudioSessionDAO(object):
    def update(self, data):
        audio = AudioSessionModel.query.filter(cs_id == data['CSID'], session_id == data['Session'])
        audio.description = data['Desc']
        db.session.commit()
        return audio

此 upate 函数在我的端点中针对 PUT 请求调用：

@api.route('/OperatorAccessment')
class OperatorAssessment(Resource):

    @api.expect(assessment)
    def put(self):
        as_dao = AudioSessionDAO()
        as_dao.update(request.json)

模型 assessment 看起来像这样：

assessment = api.model('Operator Assessment', {
    'CSID': fields.Integer(required=True, description='Central Station ID'),
    'Session': fields.Integer(required=True, description='Session ID'),
    'Desc': fields.String(description='Description')
})

当我在请求正文中使用以下 json 测试 PUT 请求时：

{
   "CSID": 1,  
   "Session": 1, 
   "Desc": "Siren"
 }

我收到以下错误：

  File "C:\Users\xxx_app\model\dao.py", line 63, in update
    audio = AudioSessionModel.query.filter(cs_id == data['CSID'], session_id == data['Session'])
NameError: name 'cs_id' is not defined

显然，cs_id 已定义。为什么我仍然收到此错误？

Answer 1

你必须使用class的属性，即

AudioSessionModel.query.filter(
    AudioSessionModel.cs_id == data['CSID'],
    AudioSessionModel.session_id == data['Session'])

或 filter_by 关键字参数仅使用 =:

AudioSessionModel.query.filter_by(
    cs_id=data['CSID'],
    session_id=data['Session'])

见What's the difference between filter and filter_by in SQLAlchemy?

为什么我会得到在 SQLAlchemy 模型中定义的列的 NameError

Why do I get NameError for the column that is defined in SQLAlchemy model

python

sqlalchemy

nameerror

flask